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//@run-rustfix
#![warn(clippy::option_if_let_else)]
#![allow(
unused_tuple_struct_fields,
clippy::redundant_closure,
clippy::ref_option_ref,
clippy::equatable_if_let,
clippy::let_unit_value,
clippy::redundant_locals
)]
fn bad1(string: Option<&str>) -> (bool, &str) {
string.map_or((false, "hello"), |x| (true, x))
}
fn else_if_option(string: Option<&str>) -> Option<(bool, &str)> {
if string.is_none() {
None
} else if let Some(x) = string {
Some((true, x))
} else {
Some((false, ""))
}
}
fn unop_bad(string: &Option<&str>, mut num: Option<i32>) {
let _ = string.map_or(0, |s| s.len());
let _ = num.as_ref().map_or(&0, |s| s);
let _ = num.as_mut().map_or(&0, |s| {
*s += 1;
s
});
let _ = num.as_ref().map_or(&0, |s| s);
let _ = num.map_or(0, |mut s| {
s += 1;
s
});
let _ = num.as_mut().map_or(&0, |s| {
*s += 1;
s
});
}
fn longer_body(arg: Option<u32>) -> u32 {
arg.map_or(13, |x| {
let y = x * x;
y * y
})
}
fn impure_else(arg: Option<i32>) {
let side_effect = || {
println!("return 1");
1
};
let _ = arg.map_or_else(|| side_effect(), |x| x);
}
fn test_map_or_else(arg: Option<u32>) {
let _ = arg.map_or_else(|| {
let mut y = 1;
y = (y + 2 / y) / 2;
y = (y + 2 / y) / 2;
y
}, |x| x * x * x * x);
}
fn negative_tests(arg: Option<u32>) -> u32 {
let _ = if let Some(13) = arg { "unlucky" } else { "lucky" };
for _ in 0..10 {
let _ = if let Some(x) = arg {
x
} else {
continue;
};
}
let _ = if let Some(x) = arg {
return x;
} else {
5
};
7
}
// #7973
fn pattern_to_vec(pattern: &str) -> Vec<String> {
pattern
.trim_matches('/')
.split('/')
.flat_map(|s| {
s.find('.').map_or_else(|| vec![s.to_string()], |idx| vec![s[..idx].to_string(), s[idx..].to_string()])
})
.collect::<Vec<_>>()
}
// #10335
fn test_result_impure_else(variable: Result<u32, &str>) {
variable.map_or_else(|_| {
println!("Err");
}, |binding| {
println!("Ok {binding}");
})
}
enum DummyEnum {
One(u8),
Two,
}
// should not warn since there is a complex subpat
// see #7991
fn complex_subpat() -> DummyEnum {
let x = Some(DummyEnum::One(1));
let _ = if let Some(_one @ DummyEnum::One(..)) = x { 1 } else { 2 };
DummyEnum::Two
}
fn main() {
let optional = Some(5);
let _ = optional.map_or(5, |x| x + 2);
let _ = bad1(None);
let _ = else_if_option(None);
unop_bad(&None, None);
let _ = longer_body(None);
test_map_or_else(None);
test_result_impure_else(Ok(42));
let _ = negative_tests(None);
let _ = impure_else(None);
let _ = Some(0).map_or(0, |x| loop {
if x == 0 {
break x;
}
});
// #7576
const fn _f(x: Option<u32>) -> u32 {
// Don't lint, `map_or` isn't const
if let Some(x) = x { x } else { 10 }
}
// #5822
let s = String::new();
// Don't lint, `Some` branch consumes `s`, but else branch uses `s`
let _ = if let Some(x) = Some(0) {
let s = s;
s.len() + x
} else {
s.len()
};
let s = String::new();
// Lint, both branches immutably borrow `s`.
let _ = Some(0).map_or(s.len(), |x| s.len() + x);
let s = String::new();
// Lint, `Some` branch consumes `s`, but else branch doesn't use `s`.
let _ = Some(0).map_or(1, |x| {
let s = s;
s.len() + x
});
let s = Some(String::new());
// Don't lint, `Some` branch borrows `s`, but else branch consumes `s`
let _ = if let Some(x) = &s {
x.len()
} else {
let _s = s;
10
};
let mut s = Some(String::new());
// Don't lint, `Some` branch mutably borrows `s`, but else branch also borrows `s`
let _ = if let Some(x) = &mut s {
x.push_str("test");
x.len()
} else {
let _s = &s;
10
};
async fn _f1(x: u32) -> u32 {
x
}
async fn _f2() {
// Don't lint. `await` can't be moved into a closure.
let _ = if let Some(x) = Some(0) { _f1(x).await } else { 0 };
}
let _ = pattern_to_vec("hello world");
let _ = complex_subpat();
// issue #8492
let _ = s.map_or(1, |string| string.len());
let _ = Some(10).map_or(5, |a| a + 1);
let res: Result<i32, i32> = Ok(5);
let _ = res.map_or(1, |a| a + 1);
let _ = res.map_or(1, |a| a + 1);
let _ = res.map_or(5, |a| a + 1);
}
#[allow(dead_code)]
fn issue9742() -> Option<&'static str> {
// should not lint because of guards
match Some("foo ") {
Some(name) if name.starts_with("foo") => Some(name.trim()),
_ => None,
}
}
mod issue10729 {
#![allow(clippy::unit_arg, dead_code)]
pub fn reproduce(initial: &Option<String>) {
// 👇 needs `.as_ref()` because initial is an `&Option<_>`
initial.as_ref().map_or({}, |value| do_something(value))
}
pub fn reproduce2(initial: &mut Option<String>) {
initial.as_mut().map_or({}, |value| do_something2(value))
}
fn do_something(_value: &str) {}
fn do_something2(_value: &mut str) {}
}
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